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Dawn of a new 'Maunder Minemum'? Solar Activity Drops to 100 Year Low.HT: IceAgeNow.
“The current peak in the solar cycle is the weakest for a century,” says this article in India Times.
“Subdued solar activity has prompted controversial comparisons with the Maunder Minimum, which occurred between 1645 and 1715, when a prolonged absence of sunspots and other indicators of solar activity coincided with the coldest period in the last millennium.”
Lower solar activity might also be one factor explaining some of the recent slowdown in global warming.
"The longevity of the recent protracted solar minimum, at least two years longer than the prior minima of the satellite era makes that solar minimum a potentially potent force for cooling," according to one group of climate scientists ("Earth's energy imbalance and implications" Dec 2011).
Even with the downturn in solar activity, the planet continued to absorb more energy than it radiated out into space.
Yet as the frequent revisions to the panel's forecasts demonstrate, scientists have little ability to predict solar activity accurately, even over short timescales.
The 11-year sunspot cycle, named after the amateur astronomer who discovered it in 1843, Heinrich Schwabe, is not the only cycle scientists have observed in the sun's behaviour.
In 1933, Wolfgang Gleissberg identified a super-cycle occurring every 87 years. Others have claimed to find even longer cycles. Some scientists believe the Gleissberg cycle accounts for the succession of three very weak 11-year cycles between the 1880s and the 1910s.
If that's true, and the Gleissberg cycle is being repeated, then the next solar cycle, Cycle 25, which will last into the 2020s, could see an even smaller number of sunspots and an even lower level of solar activity.
The problem is that no one knows what causes the Gleissberg cycle (and being much less frequent the evidence for it in the time series is much less than for the Schwabe cycle). Nor do they know how to distinguish between a normal Gleissberg cycle and the onset of a new Maunder Minimum.
So if a new Maunder Minimum is on the way, which the forecasters insist it is not, it is likely to catch us by surprise.
Given how little is known about variations in solar activity, it would be foolish to rely on a Maunder Minimum to offset the rise in global temperatures due to greenhouse emissions. Hmmmm.......Every time Earth has experienced an ice age large or small........... it happened ABRUPTLY!Read the full story here.
Yet as the frequent revisions to the panel's forecasts demonstrate, scientists have little ability to predict solar activity accurately, even over short timescales.
The 11-year sunspot cycle, named after the amateur astronomer who discovered it in 1843, Heinrich Schwabe, is not the only cycle scientists have observed in the sun's behaviour.
In 1933, Wolfgang Gleissberg identified a super-cycle occurring every 87 years. Others have claimed to find even longer cycles. Some scientists believe the Gleissberg cycle accounts for the succession of three very weak 11-year cycles between the 1880s and the 1910s.
If that's true, and the Gleissberg cycle is being repeated, then the next solar cycle, Cycle 25, which will last into the 2020s, could see an even smaller number of sunspots and an even lower level of solar activity.
The problem is that no one knows what causes the Gleissberg cycle (and being much less frequent the evidence for it in the time series is much less than for the Schwabe cycle). Nor do they know how to distinguish between a normal Gleissberg cycle and the onset of a new Maunder Minimum.
So if a new Maunder Minimum is on the way, which the forecasters insist it is not, it is likely to catch us by surprise.
Given how little is known about variations in solar activity, it would be foolish to rely on a Maunder Minimum to offset the rise in global temperatures due to greenhouse emissions. Hmmmm.......Every time Earth has experienced an ice age large or small........... it happened ABRUPTLY!Read the full story here.